Marine Electronics

Chelsea Sensors to Gather Data For WaveSentry Project
Sensors from Chelsea Technologies Group (West Molesey, England) will be fitted to a French ferry to collect vessel motion data as part of the WaveSentry project, an information tool for managing risk of marine operations in adverse sea states, Chelsea Technologies Group announced in January.

This motion data will be processed to derive certain indirect sea state measurements, which will be merged with other data feeds within the WaveSentry system managed by Marine South East (Southampton, England).

As part of the WaveSentry project, the sensor box will be fitted to a Transmanche (Dieppe, France) ferry, the Seven Sisters, which crosses the English Channel daily. The data collected from the ship will be relayed to the shore and analyzed using software from QinetiQ (Farnborough, England) to infer the sea state from the ship's motion throughout the crossing. The sensor box will collect data for about a year, Chelsea Technologies Group said.

The data collected will be logged against the GPS position of the ship and will be merged with additional data streams by HR Wallingford (Wallingford, England) to enable more accurate "nowcasting" and forecasting of sea state, including wave height, period, direction and steepness. For more information, visit www.chelsea.co.uk.

Canadian Scientists Collect Arctic Data with UnderwayCTD
Oceanscience Group (Oceanside, California) has supplied scientists on the Canadian icebreaker Sir Wilfrid Laurier with its UnderwayCTD system to collect high-quality data while en route to the Arctic, the company announced in December.

The technology allowed Canada's Department of Fisheries and Oceans (DFO) scientists from the Institute of Ocean Sciences to collect 400-meter CTD profiles without stopping or slowing the icebreaker. In the past, DFO scientists have used expendable CTD probes, launched from the Laurier while slowing the ship to 9 knots from its cruising speed of about 11 knots. While expendable CTD probes are easy to deploy, they are not as accurate and detailed as the Underway CTD, Oceanscience said.

DFO scientist Svein Vagle said, "The UnderwayCTD allowed us to obtain calibrated, high-resolution data; something that was not possible with the earlier use of expendable CTDs. We found it was actually faster to use this completely recoverable profiler system than a one-off expendable probe."

On the route from Canada to the Aleutian Islands across the Pacific, UnderwayCTD profiles were collected around every six hours with the operation completed in about 25 minutes for each 400-meter vertical profile, Oceanscience said.

The data have given the DFO the most detailed picture of the polar front, which surrounds the Subarctic Zone in the center of the Gulf of Alaska Gyre, to date, Oceanscience said. The polar front is a result of lower surface stratification combined with winter cooling and stroms to create an approximate 100-meter-deep water mixed layer. In the summer, the remnant winter mixed layer can be seen as subsurface temperature minimum near 100 meters' depth.

After crossing the Aleutian Islands, plans called for shallow water sampling and CTD profiling, Oceanscience said. For more information, visit www.oceanscience.com.

TRIAXYS Wave Sensor to Help Marine Observing Program
AXYS Technologies Inc. (Sidney, Canada) has partnered with its Australian representative, Metocean Services International Pty Ltd. (Hobart, Australia), to supply the Commonwealth Scientific and Industrial Research Organisation (CSIRO) with a TRIAXYS Directional Wave Sensor for Australia's Integrated Marine Observing System (IMOS).

The sensor was installed on the Southern Ocean Flux Station Weather Buoy, which is located south of Tasmania at a depth of 4,323 meters, AXYS said in January. The buoy, designed by the Woods Hole Oceanographic Institute, was recovered in June and was then retrofitted and upgraded to include the TRIAXYS wave sensor. It was redeployed in late November.

JW Fishers Equipment Used in Asian Underwater Search Projects
In the past year, various companies and government agencies in Asia have acquired underwater search equipment from JW Fishers (East Taunton, Massachusetts), the company said in December, citing several examples. The equipment has primarily been used to locate lost objects and assist in performing survey operations.

Examples include China's Guangzhou Advanced Maritime Academy purchasing a JW Fishers SeaLion ROV to assist in underwater training operations such as inspecting ship hulls and propulsion systems, and the integrity of seawalls at Chinese ports. Sonar Tech Co. Ltd. (Busan, Korea) is using JW Fishers' PR-1 acoustic receiver to help locate towed equipment and measuring instruments that are anchored to the seafloor, the company said. The PR-1 pinpoints the position of missing devices by detecting a signal transmitted by an acoustic pinger that is attached to the equipment.

NAVA19 Engineering Co. Ltd. in Thailand is using JW Fishers CT-1 cable tracking system to locate Short-Time Fourier Transform underwater power and communication cables. The tracking system can be carried by a diver or deployed from a boat and detects the injected signal at a range of 10 meters.

Other Asian companies that have acquired JW Fishers equipment include China's Tianjin Science Instruments and Equipment Corp. (Tianjin, China), which purchased a dual-frequency side scan sonar, and Bekk Solutions Ltd.'s (Hong Kong), which bought a PT-1 pipe tracker to locate and track buried pipes and cables. For more information, visit www.jwfishers.com.

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